Dividend-divisor aligning



G. W. HOPKINS ETAL DIVIDEND-DIVISOR ALIGNING MECHANISM 8 Sheets-Sheet l ulllilillllllllzrlb INVENTORS GEORGE W. HOPKINS ELWOOD A. DAVIS g.

GOTTFRIED ZICKLER Jan. 19, 1954 Filed Jan. 26, 1951 n am-Hum.

1954 e. w. HOPKINS ETAL DIVIDEND-DIVISOR ALIGNING MECHANISM s Sheets-Sheet 2 Filed Jan. 26, 1951 Jan. 19, 1954 G. W.'HOPKINS ETAL DIVIDEND-DIVISOR ALIGNING MECHANISM 8 Sheets-Sheet 3 Filed Jan. 26, 1951 wm ham mum I mum M m. m Qwm 4 a .mmma E y? OWN mvsurons GEORGE w. HOPKINS ELWOOD A. DAVIS g 4 GOTTFRIED ZICKLER TURA/EY 1954 G. w. HOPKINS ETAL DIVIDEND-DIVISOR ALIGNING MECHANISM Filed Jan. 26, 1951 8 Sheets-Sheet 4 INVENTORS GEORGE W. HOPKINS ELWOOD A- DAVIS GOTTFRIED ZICKLER ATTORNEY 1954 G. w. HOPKINS ETAL I DIVIDEND-DIVISOR ALIGNING MECHANISM Filed Jan. 26, 1951 8 Sheets-Sheet 5 S R W N SM E Jw HDZ OWT El-o

Jan. 19, 1954 w op s ET AL 2,666,580

DIVIDEND-DIVISOR ALIGNING MECHANISM Filed Jan. 26, 1951 8 Sheets-Sheet 6 I37 I3! I33 14' I35 I38 I35 4 I22 I30 I25 12! I29 123 124 92 INVENTORS GEORGE .w. HOPKINS ELWOOD A. DAVIS I *1 O sor-rmglso ZICKLVEZ ATTORNEY 1954 w. HOPKINS ET AL DIVIDEND-DIVISOR ALIGNING MECHANISM 8 Sheets-Sheet '7 Filed Jan. 26, 1951 mmm wK w A m Mm M fiw mm- INHIH rroRA/EY 1954 G. w. HOPKINS ETAL 2,666,580

DIVIDEND-DIVISOR ALIGNING MECHANISM Filed Jan. 26, 1951 8 Sheets-Sheet 8 FIEi IE- I49 I46 I46 9 I66 INVENTORS seams: w. HOPKINS ELWOOD A. DAVIS GOTTFRIED ZICKLER Patented Jan. 19 1954 DIVIDEND-DIVISORALIGNING. MECHANISM Application January 26, 1951', Serial No. 2i1 '7,958" 8- QIaims-.. (01.. 235.---63.)=.

This inventionrelates'to a division mechanism for calculating machines, and more: particularly to -an" improved means for'automatically aligning the dividend and divisorin such a machine as part of an automatic division operation.

In performing division operations on. calculata ing'machines of the type having relatively shiftabledivide'nd and divisor receiving devices, it has been necessary in the past for the operator" of the machine to enter the: dividend and divisor factors into the machine and then to manually control the shift of the factor receiving devices relative to one another until the factorsare brought into proper alignment before beginning an automatic division operation. The division mechanism is then set into operationby manipu'slation of a suitablecontrol" key on lever and. the machine proceeds to divide the dividend by the divisor in afully automatic manner without requiring any further attention-on the part of the operator, The: instant invention deals with an improved means for rendering the: operation of such a calculating machine more completely automatic by causing the dividend and divisor to be properly aligned prior tothe outsetaof" the division operation proper. In describing the construction and operation of the instant; invention, the terms right shift and rightmostor extreme right end position refer to the: carriage; shift operation as viewed from the operators normal position in front of the'machine keyboard;

- It is an important object of the present invention, therefore, to provide an improved means forfi'rst aligning the dividend and divisor factors in a calculating machine by causingthe register 6 carriage thereof to be shifted to its rightmost end position before automatically initiating operation of the automatic division mechanism of the machine.

It' is another object of .the invention to provide an: improved 'me'ans forautomatically aligning the dividend and divisor factorsv in a calculating machine and then dividing: the former by the lat;- terin an uninterrupted, series of sequential operations by causing the machine to automatically shift the register carriage to its rightmost end position and by delaying operation of the automatic division mechanism thereof until after the right shift operation has been. completed.

It is a further object of the invention. to pro vide an improved means of aligning preselected .dividendand divisor factors-in a calculating ma.-

chine and then dividing the former by the latter as part of a single continuous operation by automatically engaging and. locking the carriage shift mechanism of themachinein its rightshift position without initial operation ofthe automaticdivision mechanism, and then automatically=terminating theright shift operation and concurrently initiating operation of the automatic division mechanism after the shiftable carriagehas reachedits extreme right end-position.

It is also an object of" the instant invention to provide improved mechanism for automatically carrying out a division operation by first causing thecarriage of a calculating machine to be shifted continuously toward the right, terminating the right carriage shift operation automatically after the carriage. has reached itsrightmost end position, and then automatically initiating operation of; the division mechanism of: the machine for causing ordinal. shift of the carriage progressively toward the left to first automatically align the: division. factors and then divide the dividend factor by the divisor factor in an uninterrupted series of sequential operations, and in this respect is an improvement over the co: pending application of' Hopkins and Shackleford, Serial No. 200,656, filed December 15', 1950.

A further object of the present invention is to provide means in a calculating machine having a, counter-control mechanism and an automatic shifting means for setting the counter-control mechanism and locking it in such adjusted position throughout the operation of the shifting means.

Further objects are to provide a construction of maximum simplicity, economy, and ease of assembly and disassembly, also such further objects; advantages, and capabilities as will fully appear and as are inherently possessed by the device. and the invention described herein.

The invention further resides in the combination, construction, and arrangement of parts illustrated in the accompanying drawings, and while there is shown therein a preferred embodiment thereof, it is to be understood that the same is'illustrative of the invention and that the inven-. tion is capable of modification and change and comprehends other details of construction without departing from the spirit thereof.

Referring to the drawings:

Fig. 1 is a longitudinal sectional elevation showing the right shift control mechanism and basic selecting and actuating mechanisms of the machine.

Fig. 2 is a view showing those parts of the divi sion control mechanism which are mounted on the left-hand side of the control-"plate.

Fig. 3 is a view of those parts of the division and counter control mechanisms which are mounted on the right-hand side of the control plate.

Fig. 4 is a view similar to Fig. 3 showing a portion of the control means for releasing the automatic division mechanism when the carriage is in its rightmost end position.

Fig. 5 is a right side view of the right side frame showing the mechanism for operating the mainmechanism after the carriage has reached its rightmost end position.

. Fig; 8 is a fragmentary rear view of the machine showing a portion of the control mechanism illustrated in Fig. '7.

The machine to be hereinafter shown and described is basically the same as the calculating machine shown in U. S. Patent No. 2,229,889, issued to Carl M. F. Friden on January 28, 1941, and hence, only so much of the mechanism shown and described in the aforesaid patent will be set forth herein as is necessary in order to provide a complete understanding of the manner in which the present mechanism is related to that shown in the aforementioned patent.

Selecting and actuating mechanisms Referring now to Fig. 1 of the drawings there is shown a calculating machine provided with a plurality of rows or banks of amount keys 20, each of which is supported for endwise longitudinal movement by a pair of oblong slots 21 adapted to coact with the crossrods 22 which are transversely supported horizontally across the keyboard frame. The keys 2!! in each bank are resiliently urged into their raised positions by means of a longitudinally extending coil spring 23 supported by the keyboard frame in such a-manner that the spring is threaded over the upper crossrods 22 and under the pins-24 provided on the stems of the keys 20.. The lower ends of the key stems carry studs 25 which are adapted to cooperate with inclined cam faces 26 provided on the longitudinally disposed selector bars 21. There are two such bars associated with each bank of keys in the keyboard, and each bar 21 is horizontally supported for endwise reciprocating movement below the keyboard by means of a pair of parallel links 28, the rear ward supporting links shown in Fig. 1 being pivotally connected at their upper ends to their selector bars 21 and pivotally supported at their lower ends on a transverse rod 29 supported by an angle bar 30 which extends transversely across the machine.

Each of the selector bars 21 is resiliently urged toward the rear of the machine by a spring tensioned between the lower end of each of the rear supporting links 28 and an angle bar extending between the side frames of the machine. At their rearward ends, the selector bars 21' of each pair are provided with bent over and downwardly depending forked extensions 31 which'engage with coacting grooves provided in the hubs of a pair of selector gears 38 which are slidablyand nonrotatably mounted on a square shaft 39which-is suitably journalled at its ends in the crossframe members 40, 4 I, and intermediat it nds is 10 1.-

4 nalled in a bearing provided in an intermediate. crossframe 42 extending transversely across the machine.

The selector gears 38 are arranged to cooperate with a drum-type actuator 45 secured to an actuator shaft 46 which is journalled between the crossframe members and 42. The shaft is driven by a bevel gear fixed to its forward end 41,

said gear meshing with a bevel gear 48 secured to a unidirectional main drive shaft 49. Also secured to each actuator shaft 46 in a position immediately behind the first drum is a second ac tuator drum 50 which is adapted to similarly cooperate with a pair of selector gears controlled by an adjacent bank of amount keys 2B.

As is more fully shown and described in the aforementioned Patent No. 2,229,889, the drums 45 and 50 are provided with a series of mutilated actuator'teeth 52 which serve to rotate the selector gears 38 by differential amounts whenever the latter are slid forwardly on the square shaft 39 and into cooperative driving relationship with the drum teeth 52. As is fully described in the lastmentioned patent, the 1-5 keys 20 control the selector gears associated with the forward end of the actuator drums 45 and 50, while the 6-9 keys control the selector gears associated with the rear end of the actuator drums. When one of the 1-5 keys or one of the 6-9 keys is depressed, its associated selector bar or slide 21 is moved forwardly by a differential amount through the cooperation of the key stem stud 25 with its associated inclined cam face 26, so as to cause the corresponding selector gear 38 to be differentially positioned with respect to its associated actuator drum. The actuator teeth 52 on the drums 45 and 5!] will therefore rotate the selector gears 38 and the associated square shaft 39 to an extent depending upon the value of the particular keyboard key 20 which has been depressed.

Slidably and nonrotatably mounted on the rear end of each square shaft 39 is a sleeve 55 to which is secured an add gear 56 and an oppositely disposed subtract gear 51, which gears are arranged to cooperate selectively with a bevel 58 secured to the lower end of a coaoting dial shaft 59, the latter being suitably journalled in the frame 60 of the shiftable numeral wheel carriage. Secured to the upper end of each dial shaft 59 is a numeral wheel 6| bearing the numerals from 0-9, which may be viewed through a suitable aperture or window 62 provided in the shiftable carriage housing The add and'subtract gears 56 and 51 are normally maintained in a neutral position and out of engagement with the bevel gears 58 by the action of a conventional spring actuated centralizing mechanism 64 (Fig. 4) which yieldingly tends to maintain a transverse gate control shaft 65 in the neutral position illustrated in Fig. 1. Shaft 65 is suitably journalled in the side frames ofthe ma.- chine' and-has secured thereto a pair of. upwardly extending spaced arms 66'which support, parallel with the axis. of shaft 65, a strap or gate 61 lying within thespa'ce'existing between the add and subtract gears 55 and 51. Whenever gears 56 and 51 aremaintained in their neutral position by the action of centralizer 64, as shown in Figs. 1 and 4, the numeral wheel carriage 68 may be shifted laterally acrossthe machine without interference from add gear '56-'or subtract gear 51. However, by; means of 'mechanism to "be hereinafter more fully described-the gate 61'may be moved rearwardly so as to engage add gear 56 with bevel gear SBso-that upon rotation of the actuator shafts 46 uwheels il will be rotated in a oslt' H d J 11 forward n v, flm fi ch nism Seoured to the "lower end of -each dial .shar-ft i .59 iust above the gear 58, .is .a transfer 'cam 710 which is adapted to cooperate with witha transr fer lever H, bearing a stud 12, which is Jour: ia e in th carriage frame bar 50. Mounted ,on the outer end of the transfer lever -'H is is,

downwardly depending pin .13 which lies between a, pair .of flanges provided .on the hub 74 of a tens-transfer gear located in the next higherorder of the machine. The hub 14 and the gear 15 are slidably and nonrotatably mounted on the square shaft 39 (in such amen.- ner that vrotation of the vgear -15 will be transmitted through the add.,-.sub tract gears 56,15 to the ,eoacting dial shaft 59. When the aecumnr letor numeral wheel 6,! passes :from -9 .or iron; 9:0, a single tooth vor nose on the transfer cam 1g is operative to rock the transfer lever 1| and nove the pin 13 forwardly so as -.to move the transfer gear 15 longitudinally into the path ,of n l tran r te h provided on a te sl f er aqtuator 16 secured tpthe actuator sha-ft v45. Since pin 13 is operative to control the trans: {ier gear 15 in the next higher order ,of the-ma: ehin, the accumulator wheel 6] in the next higher order will be advanced one step by the tensetransfer actuator 15 in such a manner as to effect the tens-carry ,irom one order to the next higher O d r s re u redm han sm al ul d i e in Patent No. 2,229,889, 31 m n i e R velatio 9 24 l vi e i the nume al. Wheel Barthe fif ia' e rev utions c un w 7, Us go, h. Q which s ec red to a ng tu nal y ex: t n'e shaft 8| hav n its op osin ends uitab l eu n ll d i t e qerriaeeh th Whee dQd'WiE series. nun; v m which a be vi we a w id w 83 provided n t e ea aee cover or time a ing 63. Secured to each 7 9f the eheits a! in P i o aid a rl to t ele 8.! s 911 a; tor T e 18 wii 'elii s rran d n qepiier te w th a revolutions counter aetgator meehanism B e 9 d ime It??? A plus key Q0 and a minus lgey v a e siiaabi'imdilht a heel l, sio'n'o'r either of t e y go! ge the'le eg @l? t... meter e ted o th uppe ends v0f t ms 5- he term :83 ein Y e q o late 3. whi e t e a ks the at ,sha 6 y 13! mov s the ate :in 1. l1 a man er ise Five-s1 the eby mat -61 to 6 to en a e h e t y depressi n e br n s :s ud :94 into en ec iei sent-at :95: th r y paus- 9Y5 3 nwa and r tate :ea e elo wise QFig. 1-,) l sp as to o. 5: 1 ieeeeeementwith .ml ihiiiem :Q he e bine "when eit r ,of the .9 t a ke fifl o -fi de re s d each o 'the e ke t mmed w th e ha f-ro nd stud 102 whi h a apte to repo e a wi h a cam face we provided o the cyei in tiatin slide I04,

,A i i u h shewn nd des ib d in the re-; mentioned Eriden Patent No. 2,229,889, at. w e w ns th ipin J12 arried by clutch control lever I05 (Fig. 5) in such amam he that wh neve e the o he control ke 99 or 1 e ie essed th e ide I 4 ll e oved earward-1y s9 t :rqck the clu h pi i si le er 1 lockwi e ,tFito cause en a em nt o th m in y li -ela eli 19. c ut h c n ol l v M 5 is i ote at J09 on 511d? frame v and i e o iee in c es "b e lin 11 1 h a pi ote 1 408, The lever M8 i et l y c nne t d, by 1% P 1 0. exte din throu it suit b e pent9.; e e.link no ad pted to e. 9 m eonta ts of {a misreswi 1} U! (see 9i 1-ifim- The iteh om 1 hole pui en ei i p ied o the e e tric m t r 85 e- D he -drivesthe machi ea h w t A, the e pe ive right t i 9! Ke s H H5 uitably "V? endin mt ifiimfifil the 9;? b s tetl tie ens! s ot ennee t e are resi ient weed upwardly to their Ye e 11 s iieri by su abl s r n o E i t key U rovided with a pin it w th project e the side oi t e as eee atesi hey the eut reml 9f e pi H8 bein l d, 9 .Q m I h e wheel tehew is on: gluten eontrol lever [55 s eei'eseieh 9 e th r s i t le ee? U31 a H18 are re d in the me sly des ed to a e e vv t wt in and close the .shaft I22 which carries a depending arm normally open micro-switch III (Fig. 6A) for operating the driving mechanism of the machine.

Prior to engagement of clutch I06 and closure of micro-switch III, each of the shift keys" II5, I is operative to engage corresponding shift drive connections so that selective shifting of the carriage 66 in either direction for one or more ordinal positions is-determined'by depression and. release of the respective shift keys. As shown in Fig. 6A, the inner ends of the pins II8 carried by the shift keys H5, H6 are operatively related to the rocker arms I20, II9 which are carried respectively by the sleeve I2! and shaft I22 on which sleeve I 2I is pivotally mounted.

As shown in Figs. 1 and 6, sleeve I2I also carries and arm I23 for causing pusher link I25 to move the push rod I32 rearwardly. Depression of the left shift key H6 acts through arm H3 to rock I29 similar to arm I23 on which a spring-urged pusher link I30, similar to pusher link 225, is pivoted for engagement with a left shift control rod I (Fig. 6). v

The respective push rods I32 and $39 upon de pression of the respective shift keys H5, H9

serve to enable respective drive connections from one of the extended actuating shafts Mia to a shift drive plate I46 in a manner now to be described. As seen in Fig. 6, each of the push rods I32 and I36 has secured to the rear end thereof the respective forked arms I33 and I31. Suitable compression springs I34 on the respective rods I32 and I36 tend to maintain each such push rod connection forwardly in clutch-disengaging position. Forked arms I33 and I3? engage ree spective annular grooves in shiftable drive estab lishing collars I3I and I38, which have endwise slidable driving engagement with coacting col-- lars !35 (Fig. 6) secured on rearward ends of the adjacent extended actuating shafts 48a. The shiftable collars IBI and I38 are provided with suitable driving teeth I39 adapted for clutching engagement with the opposed driving notches 64*] on the respective gear sleeves I41 and I42.

- As shown in' Fig. 6, gear sleeve I carries a gear 143 which meshes with a wide idler gear, not shown, which drives a large gear I44 on a compound gear assembly including a smaller gear meshing with a gear I45 on a shift drive asseme bly which includes the shift drive plate 143; Gear sleeve I42 carries a gear I41 which meshes directly with gear I44 on the drive gear assembly. 'Hence, whenever the gear; sleeves MI and 42 are driven, they serve to drive the-gear train which includes the large gear I44 and shift drive plate I46 in opposite directions. Preferably this gearing provides a drive ratio of 4 to 1, so that each rotation of the gear sleevesI' II or I42 will provide a one-quarter rotation of shift drive plate I46. As is best shown in Fig. 8, plate I46 carries four equidistantly spaced shift drive pins I48 adapted for engagement with coacting notches I49 provided in a shift rack I 50 secured to the back of theshiftable'carriage 66. Hence, for each ninety degrees of rotation of shift drive plate I46 the carriage 68 will be shifted through 8 a distance equal to the spacing between the notches I49, which is equal to the distance between the numeral wheel shafts 59 of the machine. In other words, the carriage will be shifted one ordinal space for each cycle of operation of the main drive shaft 49.

The shift control arrangement is such that depression of right shift key II5 operates through its associated linkage for engaging drive tooth I39 with its corresponding notch I40 on gear sleeve I4I (Fig. 6), thus causing rotation of shift drive plate I46 in one direction to effect righthand shifting of carriage 68. Corresp-ondingly, depression of the left shift key I I6 causes shifting of the carriage to the left by engaging tooth I39 with its corresponding notch I40 on gear sleeve I42 to rotate shift drive plate I46 inthe opposite direction.

Means is provided for automatically disabling the right carriage shift operation whenever the shiftable carriage 68 reaches its extreme right end position. For this purpose mechanism is provided for automatically lifting the pusher link I25 and moving the same out of the range of push rod I32 (Fig. 1) whenever the carriage reaches its rightmost end position. The lifting of pusher link I25 against the urgency of spring I26 is accomplished by means of an arm I55 (Fig. 1) rotatably mounted on transverse shift I56 journalled at either end in suitable brackets secured to the frame of the machine. As shown in Fig. 1, the lifter arm I55 has integrally formed therewith a rearwardly extending arm I54 which is provided with an oblong slot that embraces a pin I51 mounted on the forwardly extending arm of a lever I58 loosely journalled on gate shaft 65. Lever I50 has a rearwardly extending arm which carries a roller I59 which lies above one end of a lever I60 (see also Fig. 8) which is pivoted at I6I on a lower end of a lever I62 pivoted at I63 on the crossframe member or rear bearing plate 4I. Lever I62 has an upwardly extending arm which is provided with a formed-over ear I64 lying beneath an override pawl I65 (Fig. 8) which is pivotally mounted at I66 on the carriage shift rack I50. This pawl I65 is normally maintained in the position shown in Fig. 8 by means of a spring I61 which urges a shoulder formed on the pawl against a stud I68 on shift rack I50. When the shiftable carriage 68 reaches the end position shown in Fig. 8, the shift pins I48 engage with a cam surface I69 formed on pawl I 65 and cause the pawl to be rocked clockwise against the urgency of spring I61. The lever I62 will thereby be rocked counterclockwise against the tension of spring I10, thereby causing lever I60 to be moved toward the right as viewed in Fig. 8. Lever I60 is provided with a cam face I1I which lies beneath a roller I12 mounted on the rear bearing plate 4|. Hence, when the lever I60 is moved toward the right as viewed in Fig. 8, it will be rocked clockwise thereby elevating the rear end of lever I58 so as to cause the lifter arm I 55 (Fig. 1) to be raised and cause the pusher link I25 to be disengaged from the push rod I32. This will effectively disable the right shift mechanism and permit the compression spring I34 mounted on the forward end of push rod I32 to disengage the previously engaged right shift clutch and thereby terminate the right shift operation.

The foregoing description of the carriage shift mechanism is believed sufficient for a clear understanding of the instant invention, and reference is hereby made to Patent No. 2,380,642 issued to Carl a1. jun July 8i, 1945; 1-

e'more detailed aiscusjsure of this part of the mac ine. 7 Automatic dilution mechanism The machine shown in the accompanying drawings is provided with a mechanism for en abling a dividend set up on the accumulator numeral wheels 61 to be automatically dividedby the method of successive subtraction by a divisor set up on the amount ke'ys 20. As wasmentioned earlier herein; the mechanism provided in the present machine for accomplishing this purpose is similar to that shown in U. S. Patent No. 2,229,889, and, therefore, only those parts of the automatic division mechanism which are directly concerned with the present invention will be described herein.

The automatic division mechanism operates to control the functioning of themachine so as to cause the divisor to be repeatedly subtracted from the dividend until an overdraft occurs in the accumulator, whereupon the overdraft is corrected and the carriage is then automatically shifted one ordinal space to the left. This sequence is continually repeated during the division operation and the number of subtraction cycles effected in each order is registeredin the revolutions counter as the quotient. This division operation is controlled by the program control mechanism, which becomeseffective each time an overdraft occurs inthe' accumulator and functions" to program the operation of the addisubtract mechanism and the carriage shift mechanism in sucha manner as to cause a'predetermined; sequence of operations during un; interrupted cyclic operation of the division mechanism The division operation is v initiated by rocking the division controilever 252 (Fig; 3), n a manner i0b' x aterr ssribed. z hi v p rai au rrbsr m. eei lm q ani mie be e ai i ly cen sst dfl ih add-subt ac gate and the;carria'ge ,shift mechanism by" engagement of the cam face 282 with the pin 28! (Fig. 2). It also renders the overdraft control mechanism irect'ive'to control the operation of the program control mechanism. i'llsu'cli op: erations are shown and described in Patent No. 2,321,981, issued to Carl M. Fr'iden on August 31, 1943.

The divisionm'echanism of the: machine in-' cludes alink 26 9'wfiich' is pivotally connected as at 261' tome forward end of a connecting lever 210 (Fig. 2), which eve'r is 'pivotedasa't'21'l] to a follower armj 212 pivoted as at 213 on control plate 32'. This arm 2 12' is spring-urged in a clockwise direction (spring not shown); as viewed idFig. 2; and isprovided with a" square aperture 215 within which is locatedan eccentric came-1's secured to 'a programclontrolling shaft 211, corresponding toshaft 222 in thef above'- mentioned Patent no; 2327;981. 1 As is rnore fully described in the pat nt, shaft'211j forms a" part of the program control mechanismfandis rotated intermittently duri g; divisi in"; operations in such a-mann'en as to control e setting of the addsubtract gate 61 and"; t operation-of the left shift clutch, which operations: are per'fo n ed in a prfltbrmineif sq n 9: a l's? the machine" to' carry out a?" division operation in-a' fully auto'rnaticm Lever 2'10-is' prov de a n a y' d e 289' ge.- .i wh i bifurcatedat'i tremityfor' thepiurpos'e setting slide 91. A pin I16 extending laterally outwardly from arm 280 carries a roller I11 (Fig; 3) which engages with a cam face I18 on the division control lever 262 so that as lever 26.2 is rocked, in a manner to be hereinafter described, it causes lever 210 to be rocked clockwise (Fig. 2) When the control shaft 271 is in the normal or home position illustrated in Fig. 2, cam 216 thereon causes arm 212 to be main tained in its most forward position. Thus, when lever 211fl is rocked clockwise an inclined cam face 282 provided on the rear lip of the bifurca tion engages with stud 28! and forces gate setting slide 91 into its forward position so as to engage the subtract gears 51 with the dial shaft gears 53. Mounted on the arm 280 and extending in,- wardly therefrom is a'half-round stud 283 (Fig. 2) which is adapted to be engaged by a spring: pressed latch, not shown, so as to retain lever 210 in its operative position throughout the division operation. I v

Pivotally connected to the upper end of link 269 is the rearwardly extending arm of a bellcrank lever 290 (Fig. 2) which ispivotally supported at its forward end by a screw 29! secured to control plate 32. This lever 29!] has an upwardly extending right angle extension which lies immediately in front of a pin 2&2 carried by the cycle initiating slide 164. Lever 298 is urged clockwise (Fig. 2) by a spring 293 which also urges link 269 upwardly, and thus tends to maintain lever 210 in the normally inactive position shown in Fig. 2. Ro'eking of lever 230 against the tension of spring zts causes the upper arm of the lever to push against pin 292 and move slide [04 rearwardly. This'movement of slide l4, operating through pin H2 (Figs. 2 and 5) rocks clutch pawl m5 to engage the main drive clutch, and acts through link H31, arm I03, and link H0 (Fig. 6A) to close the motor switch H l, in the manner previously described. 7

Referring now to Figs. 3 andd, it will be noted that program control shaftj2'11 extends through control plate 32 and has secured to its righthandend asmall mutilated gear 298. This gear is positionable in driven relationship with a' larger segmental gear 2% (Fig. 3) secured to a conventional gear 300, the latter being rotatably j ournalled on a screw 291 mounted on the control plate 32. Gear 308 meshes with gear 251 carried by main drive shaft 49, with the result that gear 251 drives gear 300 and the large segmental gear 299 associated therewith whenever the mainclutch lfiii'is engaged. The small mutilated gear 298' is normally located in an inopera tiveposition wherein it lies out of the plane of the larger segmental gear 299, which position is de-' termined' by a notch provided in gear 293 engaging over a-pin 29B projecting outwardly from the control plate 32. As viewed from the front of the machine, shaft 211 and the small mutilated'gear 298' carried-thereby are normally urged to' the left by a suitable compression spring, not shown,-,mounted on the left-hand end of the shaft 211. With the shaft 2.11 in its leftward position the notch in gear 298 engages pin- 2% and permits the small mutilated gear 298'to lie tothe left of the large segmental gear 299. 'As

shown in Fig. 3, gear 298 has three sets of three teeth, each set being adapted for cooperation with'a single' se't of two .te eth provided on-ihe- I V Gear 283 rotates; counter-clockwise during cycling of-the machine large mutilated gear 299.

but'normally doesnot' drive mutilated gear 238 as the" latter is displaced to the left thereof.-

However, when shaft 211 is forced to the right, the pin 29B holds gear 298 in the plane of segmental gear 299, so that the two teeth of segmental gear 299 are positioned to successively engage each of the sets of three teeth on gear 298, before the mutilated gear returns to its normal plane. Thus, when gear 298 is projected into the path of gear 299 during a division operating cycle, gear 298 will be rotated clockwise through one-third of a revolution at the end of the first complete revolution of gear 388, and also through one-third of a revolution at the end of each of the two next succeeding complete revolutions of gear 388.

, A stud 38I mounted below stud 283 on lever 218 (Fig. 2) lies beneath the forward end of an arm 382 secured to a laterally extending shaft 383, which corresponds with shaft 228 in Patent No. 2,327,981, supra. It will thus be seen that as connecting lever 218 is rocked clockwise (Fig. 2), pin 38! acts through arm 382 to impart a corresponding counter-clockwise rocking movement to shaft 383, as described in Patent No. 2,327,981, supra, thereby determining operation of the overdraft responsive device associated with the automatic division mechanism of the machine. As soon thereafter as an overdraft occurs in a preselected higher order such as the twelfth order of the machine, the shaft 211 will be displaced axially so as to move the small mutilated gear 298 into the plane of the associated driving gear 299. In this manner, shaft 211 will be given one cycle of movement during the next three machine cycles, after which gear 299 will drop back over the pin 296 and be returned to its inactive position.

Whenever earn 216 occupies the position marked A in Fig. 2, which is the position of the cam when the notch in the small mutilated gear 298 engages with pin 296, clockwise movement of lever 278 (Fig. 2) causes gate setting slide 91 to be moved forwardly in such a manner as to engage the subtract ears 51 with the dial shaft gears 58. At the end of the subtract cycle in which an overdraft occurs, however, shaft 211 will be rotated counter-clockwise (Fig. 2) through 120 to the position marked B, with the result that arm 212 will be rocked counterclockwise and move lever 218 toward the rear of the machine, thereby causing the add-subtract gate 61 to be moved to its add position. As is fully shown and described in the afore-mentioned Patent No. 2,327,981, during the next machine cycle the divisor set up on the amount keys 28 will be added back into the accumulator dials, thus correcting the overdraft, and at the end of this correction cycle shaft 211 will be rotated through another 120 to the position marked C, in which latter position cam 216 moves arm 212 to an intermediate position for determining a Single order left-shift operation wherein the add-subtract gears 56 and 51 are held out of engagement with the coacting dial shafts 58 during shifting movement of the carriage.

The above-described mechanism is substantially the same as that described in Friden Patents Nos. 2,229,889 and 2,327,981, supra, to which patents reference may be had for a more complete description thereof.

There is also provided mechanism effective during operation of the machine for locking the revolutions counter mechanism in such a position as to selectively determine either like or unlike registration in the accumulator and revo- 12 lutions counter. Forthis purpose, there is indicated generally at 254 (Figs. 3 and 4) a countercontrol mechanism of the type shown and described in Patent No. 2,294,111, granted to Carl M. F. Friden on August 25, 1942, wherein a pivoted control arm 180 operatively connected with the slide 97 and the gate control shaft 65 is provided with a forked forward end carrying a pin 181 which is normally urged by a spring 182 into engagement with a coacting slot 183 on a counter setting member 184, thus normally determining like registration in the accumulator dials 61 and revolutions counter dials as described in the patent.

Although the counter-control setting illustrated in Figs. 3 and 4 is sometimes used in performing division operations wherein complementary quotient figures are desired, the operation of the counter-control mechanism normally must be reversed to determine unlike registration in the accumulator and revolutions counter while performing most division operations in order that true figure quotients will be obtained. For this purpose there is provided a counterreversing key 244 (Fig. 3) which when depressed rocks bellcrank I counter-clockwise about its pivot I86 by engagement of the cam face I81 with a stud I88 on the key stem, thus moving the control link I89 forwardly against the tension of return spring I98. The rear end of the link I89 is pivotally connected to a bellcrank indicated generally at I9I by any suitable means, such as the pin shown. As bellcrank I9I is rocked counter-clockwise about its pivot I92 by the control link I89, a rearwardly extending finger I93 on the bellcrank engages with and lifts pin I8I out of the coacting notch I83, against the tension of spring I82 and rocking the control arm I88 clockwise about its pivot I19 (Fig. 3) until the pin I94 on the lower fork of arm I88 engages the coacting slot I95 on the member I84, thus conditioning the counter-control mechanism for unlike registration in the revolutions counter with respect to the accumulator as described in the above-mentioned Patent No. 2,294,111.

For locking the counter-control mechanism in one of its two adjusted positions during operation of thecalculating machine, there is provided a bellcrank I96 (Fig; 3) which is urged by a spring 285 in a clockwise direction about its pivot I91 so that an ear I98 on thebellcrank engages with one of the notches 288, 28I on a downwardly and forwardly extending right angle extension 282 provided on the countercontrol link I 89. Whenever the machine is in its full-cycle position, an ear 283 on a flange 284 (Figs. 3 and 5) which extends laterally outwardly from link I81 rocks bellcrank I96 counter-clockwise (Fig. 3) against the tension of its spring 285 to release ear I98 from looking engagement with the notches 288, Ml so that the setting of the counter-control mechanism 254 can then be easily changed by suitable control means, as by depressing the counter-reversing key 244. This key preferably is located on the machine in close proximity to a division control key 245 (Fig. 2) so that both keys can be conveniently depressed together in order to initiate a normal division operation. However, possible misoperation of the machine which might be caused by any attempted change in the previous setting of the counter-control mechanism is prevented by positive engagement of ear I98 (Fig. 3) with one of the notches 288, 28I on I 3 the: counter-controlluse; I09 long; as? the machines is" operating or: is out: of its full-cycle position:

Means for initiating. oper at'io'rt ofthe automatic division. mechanism Means provided for: locking the carriage right shift clutch" in its engagedposition" and; enabling operation of the;carriage"shift drive; while at the"same tiinedelaying operation ofthe automatic division mechanism of the machine until the right shift operation is'- automatically terminated after the carriage reaches its extreme right end positionz For" this purpose'there is provided a' divisioncontrol key" 205 (Figl' .2) sup"- ported-bya longitudinally disposed pair of elon gated-slots 24 6 for endwise*sliding" movementon the coacting; guide studs 2'41 carried by control plate 32. Key;245"'is-normally" urged to: its raised position by means: of a'suita'ble return springl 2481'and the key is'alsot provided with an inclined cam face'zdfl'which bears against a roller 250 mounted on a: division control slide" 251. This slide is supported for endwise slidingrnovemen-t on controlplate 32 by a plurality of'elongated slots 252'which cooperate with studs 253 mounted on the control. plate. Whenever key 245 is depressedagainst the tension of spring 203170 move slide 25I rearwardly, from its first adjusted position to its second adjusted" position by engagement of'roller 250 withthe cam face 249,.

anarm 3I3 (Fig. .1) which engages the pm 320' (Fig. l) socas to rock arm'I23 and the yieldable pusher link I25counter-clockwiseabout the axis of shaft I22, thus causing the control rod I32 'to" be rn'oveds rearwardly to "its right shift engaging position; Hence; --the -right shift "clutch mecha= nism iszlatched-in its -engaged positionuntil the right .carriage shift operation *is automatically: terminated after the carriage-6 8 reaches its extreme right end 1? position; and the "overtr'avel" responsive mechanism'thereafter rocks arm: I55 against the" tension" of spring I26 "to lift the notched =-e'nd*' I 2! of i-pusherlink I 25" out of engagement with the forward end-of the right shift clutch control rod I I 32 in" the manner previously described. During-"the'time theright "shift control rod I32 is'movedrearwardly'and held in its cluteh engaging position byi'engagement of the latch-'2 08 withthe'pin- 3 I 01(Fig. 2) a corresponding: rocking; movement is in'aparteo'l through arm" 123m sleeve IZI; therebyrocking arm I20 clock wise- (Fig; 6A) so thata downward iprojecting'.

extension 3 I8 thereonforms a'oammingl engagement with a-pin=3I9 --on one arm'of. 'a bellcrank pivotedas at 32 I= onthe side fr'an'ae92i The'other ar-m 322' of" the bellcrank bears' against the pin. I so=that clo'ckwismovement of the bllcrank' moves-the pinforwardlyjo 'r'ojck lever. I (Fig. 5); thusconcurrently jclosing 1.the .;mam; cy1ic rnicro' switc'h III Fig. 6A) to'lenableith 5y;

r iage shift drive the manner previously described:

In order to control the means for initiating operation of the automatic divisiofimechanism, there. is provided on the division control slide 2'5I an upwardly projecting right" angle extensionupper edge of which upon" rearward movement of slide 25I forms-a camming engagement with a coacting ear 351 on a -divisioninitiating pawl 352 (Fig. 3)'- s0 as'toslig-htlyitilt or rock the'pawl 3-52 counter clockw ise*aboutitspivot 353, and as lug 3 50 moves rearwardlypast the' ea'r 35'I spring 354 causes the lattei'f todrop' down behind the lug to condition activee'ngagernent therewith.

Pawl 352 has an oblong" slot 355 therein which forms a-sliding pivot connection with'the fixed pivot pin 353, the pin'being normally heldin engagement with the forward end of. slot 35 5 as" shown in Fig. 3')' byther'e'silient action" of spring" 354; Pawl 352 isalso'providedwith a roller356. and'ha's a downwardly extending rearwardtip 35'! which is freely slidable within a longitudinal groove bounded'on'oneside by'tlie forward end of division'initiating. lever 262'and on the' other side by a plate 358 having" the same general configuration asthe. forw'ardfend of lever 252, which plate is secured totlie lever 262' by a suitable spacer rivet 359. rhuspnmssa and lever 262 form a unitarystructur which is free to pivot about the pinI36'0 andfis tirged'counterclockwise'by a spring 3-6I tendingto-hold the cam face I 13 on. lever 2-b2'in resilie'nt contact with the roller I11; carried the; connecting; lever 210i Spring 354 alsotends-to rock pawl 352; clockwise about 2 its pivot.353 -so as to: resiliently hold the roller 356 on pawl 352 in freely slidably" cam-acting engagement with the coacting upper surface of the divisioninitiatingalever 262.

It will .be' recalled -thatpawl I 65 "'(Fig.' 8) imparts a-rockingi movement-to lever I during the attempted overstroke of the :-carriageshift:

mechanismwhich -0ccurs--; after the carriage reaches its extreme righ-t hand position. Such rocking of lever I60 causes the inner end thereof to elevate the roller I59 and rock the lever I 58 to rock'the lifter: arm? I55 "clockwise (Fig. 1). Such operation moves'the notched-end- I 21:01? pusher link- I25 out of holding; engagement with the shift controlrod-I32, ;whereupon rod I32 ismoved forwardly. by the-return spring-I34 (Fig.

6) so as to disengage thesright shift clutch. For automatically initiating?operationof.the automatic division 'm'echanis'm' of the machine at substantially the same: time 'as theright shift clutch is disengaged? there is pivo-tallyfm'ounted as at 324 on theirear bearing-plate a lever 323 which is adapted I to Joe rocked counter clockwise (Fig? 8)" by' the upward movement imparted to roller I53 by the well-known overtravel responsive mechanism previously described. Rockingoft lever: 323 in a counterclockwise direction' (Fig; 8) =depresses= one arm 362 of a bellcrank 365pivoted at 363. An upwardly extendingarrn-of bellcrank 365 engages a pin 364 (Fig. 4) on the upwardly extending arm of a 'second-bellcrank also pivoted on the pin 303' to-depress the'link366 which is pivotally mounted thereon at 31-3. depressed, it. rocks lever-36% clookwise about its pivot 360 (Figwiyand movescontrol link 369 forwardly against thetension 0f spring 240fto erseerr elq 1 je r 2 to e -1 As link 3661s thus coacting cam face 31I on latch 203 and rockthe latter clockwise in opposition to the action of spring 312, thus releasing the notch 201 on latch 208 from holding engagement .with the pin M on the division control slide 25 I.

Upon the release of latch 208 from engage ment with pin 3I0, slide 25I is moved from its rearward position to the forward position shown in Fig. 2 by the resilient action of the relatively strong spring 206. During this release operation, arm 3I3 is restored by spring 308 to the position shown in Fig. 1, thus enabling the spring I23 to restore the notch I21 on pusher link I25 to its full cycle position as shown. Spring 303 alsorocks shaft 3I2and causes arm 3 to be held in resilient engagement with pin 3 I0 during return movement of slide 25I to the position illustrated in 2. As slide 25I is thus moved by spring 206 from its rearward to its forward position, the forward edge of lug 350 thereon engages with the rear edge of ear 35I so as to move pawl 352 forwardly along with slide 25I, thus tensioning spring 354 and moving the rear portion of oblong slot 355 (Fig. 3) into engagement with the fixed pivot pin 353 while the roller 356 on the pawl 352 moves along the coacting upper planar surface on lever 262. This forward movement which is thus imparted to pawl 352 by engagement of ear 35I with the lug 350 brings a cam follower 316 on pawl 352 into i the operative range of a plate cam 311 which rotates with the main drive shaft 49 of the ma chine. After pawl 352 is thus moved forwardly to its active position, the high point 318 of cam 311 engages the follower 313 and rocks pawl 352 clockwise about its pivot 353, causing the pawl roller 353 to rock lever 2B2 counterclockwise about its pivot 360 (Fig. 3) so that the camming surface I18 on arm 262 cooperates with roller I11 to rock the cam face 282 on the connecting lever 210 into operative engagement with the pin 28I on the gate setting slide 91, thus initiating an automatic division operation in the manner previously described.

For enabling the pawl 352 to be restored to its normally ineffective position after initiation of the automatic division operation, there is pivotally mounted at 385 on the forward end of lever 262 a yieldable holding arm 386 urged by a relatively strong spring 381 to the position shown in Fig. 3 wherein an ear 388 on the arm normally forms a limiting engagement with the lower forward edge of lever 282. An extension on arm 338 is also provided with an ear 389 which overlies the forward end of pawl 352. Hence, when arm 282 is rocked counterclockwise to its division initiating position by the power-operated cam-acting pawl 352, the ear 389 holds pawl 352 in such a position that the ear 35I thereon is free to be urged rearwardly past the connecting lug 350 on slide 25I by the resilient action of spring 354. While pawl 352 is thus being restored by spring 354 to the initial position shown in Fig. 3, lever 262 is positively held in its division-initiating position by latching engagement of a downwardly extending dog 390 on lever 262 with an upwardly extending tip 39I on a latching arm 392 which is urged in a clockwise direction about its pivot 393 by a spring 394. Rocking of arm 392 in a clockwise direction (Fig. 3) is limited by engagement of an car 395 on arm 392 with the upwardly extending arm 396 of a bellcrank 391. This bellcrank is urged in a clockwise direction about its pivot 393 by a spring 398 which tends to hold a forwardly extending arm 399 on bellcrank 391 in resilient contact with a cam 400 secured to the outer face of gear 300 (Fig. 3). It will thus be seen that cam face 282 is held in positive engagement with pin 2! while pawl 352 isrestored by the spring 354 to the position shown in Fig. 3.

Shortly after the high point 318 of cam 311 moves past roller 316 and enables pawl 352 to be returned by the spring 354 to its normally ineffective position, the high point of cam 400 coacts with arm 399 to rock bellcrank 391 and lever 392 counterclockwise (Fig. 3), thus moving lever 392 to its normally ineffective position wherein tip 39I is unlatched and moved in front of extension 390 on lever 282 as shown in Fig. 3. It will be recalled that after lever 392 is thus released from engagement with lug 390, the rear upper end of connecting lever 210 is retained in operative engagement with pin 28I by a springurged latch, not shown, and that the connecting lever 210 is not restored to the full-cycle position shown in Fig. 2 until the automatic division operation has been completed.

We claim:

1. In a calculating machine having an automatic division mechanism, the combination which comprises an amount entering means for receiving a divisor factor, a register for receiving a dividend factor, mechanism for laterally shifting the said register in either direction relative to the said amount entering means, a positionable division control member, resilient means biasing said member to an inoperative position, manually operable means for moving said member to an operative position, means for latching said member in an operative position, mechanism controlled by said positionable member upon movement to its operative position for initiating operation of the said shifting mechanism to move the said register toward its rightmost end position, and power-operated mechanism operated by said shifting mechanism in attempted overtravel movement of the said register beyond its rightmost end position for releasing said latch and thereby terminating the said right shift operation, and means controlled by said member inits return to its inoperative position for initiating.

operation of the said automatic division mechanism.

2. In a calculating machine having a register for receiving a dividend factor, an amount entering means for receiving a divisor factor, and shifting means for laterally moving the said reg- .ister relative to the said amount entering means, the combination with an automatic division mechanism of the successive subtraction type which comprises a positionable division control member normally biased to a first adjusted position, manually controlled means for moving said member to a second adjusted position, mechanism controlled by said member upon movement to its second adjusted position to initiate operation of the said shifting means to move the said carriage toward its rightmost end position, latch- I ing means for releasably holding the said division control member in the said second adjusted position, a normally ineffective power-operated mechanism for initiating operation of the automatic division mechanism, and control means operated by an overdrive of the register shifting means in the said rightmost end position of the register for releasing the said latching means, and means operated by said member in its return to its first position for rendering the said power-operated mechanism effective to initiate operation of the said automatic division mechanism.

3. In a calculating machine having a register for receiving a dividend factor, an amount entering means for receiving a divisor factor, and means for laterally shifting the said register relative to the said amount entering means, the combination with an automatic division mechanism of the subtractive type which comprises a settable division control member normally biased to a first adjusted position, manual means for moving said member to a second adjusted position, latching means for releasably holding the said settable member in the second adjusted position, mechanism controlled by the said settable member in its movement to its second adjusted position for initiating operation of the said shifting means to automatically move the said carriage toward its rightmost end position, control means operated by the said shifting means and operable after the carriage is thus moved to its rightmost end position for moving the said latching means to release the said settable member for return to its first adjusted position, and cam-actuated means conditioned for operation by the said settable member in its return to the said first adjusted position for positively initiating operation of the said automatic division mechanism.

4. In a calculating machine having a carriage, an accumulator for receiving a dividend factor in said carriage, a revolutions counter in the said carriage, an amount entering means for receiving a divisor factor, and means for laterally shifting the said carriage relative to the said amount entering means, the combination with an automatic division mechanism which comprises a settable division control member normally biased to a first adjusted position, manually controlled means for moving said member to a second adjusted position, latching means for releasably holding the said settable member in the second adjusted position, mechanism controlled by the said settable member in its movement to its said second adjusted position for initiating operation of the said shifting means to automatically move the said carriage toward its rightmost end position, control means operated by an overdrive of the said shifting means in the rightmost end position of the carriage for operating the said latching means to release the said settable member for return to its first adjusted position, a normally inoperative cam-actuated means for positively initiating operation of the said automatic division mechanism, means operated by said settable member in its return to its first adjusted position for rendering said cam-actuated means operative, a revolutions counter-control mechanism, means operable when the machine is in its full-cycle position for adjusting th said counter-control mechanism to selectively determine like or unlike registration in the said accumulator and revolutions counter, and means for positively locking the counter-control mechanism in a preselected one of the said adjusted positions during operation of the said machine.

5. In a calculating machine having a carriage, an accumulator in said carriage for receiving the dividend factor, an amount entering means for receiving a divisor factor, and power-operated means for laterally shifting the said carriage relative to the said amount entering means, the combination with an automatic division mechanism which comprises a settable division control member normally biased to a first position, manually operable means for moving said member to a second position, a latch for releasably holding the said settable member in the second position,

18 mechanism operated by the said settable member in its movement from its first to its second position for initiating operation of the said shifting means to automatically move the said carriage toward its rightmost end position, mechanism operated by the said shifting means in attempted shifting of the said carriage beyond its rightmost end position for releasing the said latch and allowing the said settable member to return to its first position, a power-operated cam actuator, '21

cam-actuated pawl normally biased to an ineffective position beyond the range of the said cam actuator, means operated by the said settable member in its return to the said first position for positioning the said cam-actuated pawl within the effective range of the said actuator, and mechanism operated by the said actuator while the said pawl is thus positioned in its effective position for initiating operation of the said automatic division mechanism.

6. In a calculating machine provided with an automatic division mechanism including a normally disabled division initiating connecting lever, a keyboard on which the digits of a divisor may be set, and a laterally shiftable carriage having a register into which the digits of a dividend may be entered, the combination which comprises carriage shifting mechanism including a right shift clutch normally biased to open position and engageable for effecting shift of the said carriage toward the right relative to the said keyboard, means for driving the said carrlage shifting mechanism including a main drive shaft and a cyclically operable clutch, an override pawl operated by the said shifting means during overdrive in attempted shifting of the said carriage beyond the rightmost end position of said carriage, a positionable division control slide, resilient means tending to urge the said slide to a first adjusted position, manually operable means for moving the said control slide to a second adjusted position, latching mechanism for releasably holding the said control slide in the said second adjusted position, mechanism operable by said slide in its movement from its first to its second adjusted position for engaging the said right shift clutch and enabling said driving means for the said carriage shifting mechanism so as to cause continuous shifting of the said carriage toward the right, means operated by said override pawl for releasing the said latching mechanism and enabling the said control slide to return to the said first adjusted position, a division initiating cam on the said drive shaft, a positionable member normally biased to a position outside the path of travel of said cam, means operated by the said control slide in its return to the said first adjusted position for moving said member into the path of travel of the said cam, and means operated by said member for enabling said connecting lever for initiating an automatic division operation.

7. In a calculating machine provided with an automatic division mechanism including a normally disabled division initiating connecting lever,

a keyboard on which the digits of a divisor may be set, and a laterally shiftable carriage including a revolutions counter for entering the quotient and an accumulator into which the digits of a dividend may be entered, the combination which comprises carriage shifting mechanism including a'right shift clutch normally biased to open position and engageable for effecting shift of the said carriage laterally toward the right relative to the said keyboard, means for driving the said car- 1'9 riage shifting mechanism including a main: drive shaft and a cyclically operable clutch, an override. pawl operated by the shifting'means during overdrive in attempting to shift the saidcarriage beyondits rightmost end position, a positionable division control slide, resilient meanstending to urge the said slide to a first adjusted position, manually operable means for moving the said control slidetoa second adjusted position, latching mechanism for releasably holding the said control slide in the said second adjusted position, mechanism operated by the said control slide in its movement to its second adjusted position for engaging the right shift clutch and enabling said driving means for the said carriage shifting mechanism so as to cause continuous shifting of the said carriage toward the right, means perated' by the said override pawl for releasing the said latching mechanism and enabling the said control slide to return to the said first adjusted; position under the urgency of thesaid resilient means, a division initiating cam on the said drive shaft, a positionable member normal- 1y biased to ineffective position with respect to said cam, means operated by the said control slide in its return to the said first adjusted position for positioning said positionable member in an operative position with respect to said cam, means operated by said positionable member for enabling said connecting lever for initiating an automatic division operation, mechanism for restoring the said pawl to its normally ineffective position during the said automatic division operation, a revolutions counter-control mecha-- nism, means operable while the machine is in full-cycleposition .for adjusting thesaid countercontrol mechanism to selectively determine like or unlike registration .in the said accumulator andrevolutions counter, andmeansfor'positively locking the said counter-control mechanism in one preselected adjusted position asxlong as the said cyclically operable clutch remains engaged for determining operation of the said machine.

8, In a calculating machine having a register for receiving a dividend factor, a selection means for receiving a-dlvisor factor, a positionable value 2i entering mechanism. for. transmitting a value set in theselectionmeans into the register, arevolutions counter, a revolutions counter control mechanism adjustable to determine like or unlike registration in the revolutions counter with .respectto said register,,manual means forv adjusting said revolutions counter control mechanism to either its like or unlike position, shifting means for laterally moving the said register in either direction relative to the said selection means, and a drive means for said machineineluding a clutch and a clutch control member: the combination with an automatic division mechanism which comprises a positionable division control member normally biased to'aninoperative position, manual means for moving said member to an operative position and for operating said clutch-controlmember,means for latching said member in its operative position, means controlled by said member in its movement. to. its operative position for initiating operation ofthe said shifting means to move the said register toward .its rightmost end position, means operated by the shifting means in attempted overtravel movement of the said register beyond its rightmost end position for releasing said latching means and for initiating operation of the said automatic division mechanism, and means-operated by said clutch control member for locking the said counter control mechanism ineither adjusted position;

GEORGE W. HOPKINS,

' ELWOOD A. DAVIS.

GOT'I'FRIED ZICKLER.

References Cited inthe file. of this patent UNITED STATES PATENTS Number Name Date 2,365,325 Avery Dec. 19, 1944 2,365,507 Allen Dec. '19, 1944' 2,366,345 Machado Jan. 2, 1945 2,399,917 Friden May 7, 194.6- 2,408,097 Pott Sept. 24, 1946 2,636,677 Gang Apr. 28, I953 

